Formation packer



April 2 1953 G. w. NlELsoN ETAL 3,083,775

FORMATION PACKER 5 Sheets-Sheet 1 Filed Oct. 5. 1959 Tril l James D.Henderson Gurh W. Nielson lnveniors BYQ" M Attorney April 2, 19.63 G. w.NlELsoN ETAL 3,083,775

FORMATION PACKER 3 Sheets-Sheet 2 Filed 00'6- 5. 1959 GAS OIL

FIG. 4

FIG.5

James D. Henderson Gor'rh W. Nielson Inventors ByQvv Attorney April 2,1963 G. w. NIELsoN r-:TAL 3,083,775

FORMATION PACKER 3 Sheets-Sheet 3 Filed OCT. 5. 1959 FlG. 6

James D. Henderson Gorth W. Nielson Inventors ByM Attorney United StatesPatent O 3,083,775 FRMATIN PACKER Garth W. Nielson and Eames D.Henderson, Devon, Al-

harta, Canada, assignors to Jersey Production Research Company, acorporation of Delaware liled @ce d, 1959, Ser. No. 844,542 7 Claims.(Cl. 166-201) rl`his invention concerns a packer for use in well bores.It especially relates to a mechanical packer for use in an open holesection below a production casing through which the packer is run.

Well `bores are drilled in the surface of the earth to great depths in asearch Afor petroleum products, as well as water and other minerals.Usually oil wells are lined with a casing which is usually steel toprevent the crumbling of the walls of the well bore and also to preventthe entry therein of undesirable fluids from the various formationstraversed. In some instances, the casing is not set to the bottom of theborehole, but rather is set or cemented at a point above the bottom ofthe hole which is usually at the top of the formation from which it isdesired to produce fluid. In such a completed well, it is sometimesdesirable to set a packer in the open hole section in order to produceoil preferentially to water or to gas which may respectively be below orabove the oil. There are many types of formation packers available tothe industry; however, none of them are adequate to pack olf in the openhole which is larger than the diameter of the casing through which thepacker is run. It is thus seen that there is a need for a new type ofpacker which may be passed through the casing, yet expand sufficiently fo pack olf the open hole beneath the casing. The present inventionprovides such a packer.

Briefly, the invention includes: a plurality of resilient annularpacking elements spaced about a tubular mandrel and a plurality offolded metal plates set on a double traveling mandrel. Means areprovided for forcing the fol-ded metal plates into a substantiallyhorizontal position. Thus, during one travel of the mandrel, the platesare spread out so as to hold or support the resilient packing elements.Further travel of the mandrel is used to compress the packing elementsagainst the plates so that the packing elements will expand outwardlyagainst the walls of the borehole.

A fuller and better understanding of this invention may be had from thefollowing description taken in conjunction with the accompanying drawingin which:

FIG. 1A is an upper portion and FIG. 1B is a lower portion of alongitudinal section showing one embodiment of the invention in theposition it is in while being lowered through a string of casing;

lG. 2 is a horizontal section on line 2-2 of FIG. l; iFlG. 3 illustratesa horizontal view of one of the plates of FIG. l;

FIG. 4 illustrates a portion of the apparatus in an expanded positionagainst the walls of the borehole;

FIG. 5 illustrates a fragmentary View of the apparatus, illustrating theposition of plates when the apparatus of FIG. l is withdrawn from thewell bore; and,

FIG. 6 illustrates another embodiment of the invention in which supportplates are positioned above the packing elements.

Referring to the drawing, FIG. l in particular, there is illustrated acasing l@ which has been set with cement 13 at depth 12 in borehole 14.The packer assembly is attached to the lower end of tubing string 18which is suspended within the casing 10.

Attached to tubing string 18 is upper travel collar 20. A head 22 isconveniently used to connect the upper travel collar 219 with tubingstring 18. A travel adjustment screw 24, having head 25, is connected tohead 22.

3,083,775 Patented Apr. 2, 1963 "ice The extension of screw 24 intotravel collar 20 is adjustable.

An annular packerhead 26 is shown at the lower end of upper travelcollar 20 and connected thereto conveniently by threads 23. Packer head26 has an upper shoulder 27 within upper travel collar 20.

A mandrel 30 is inserted through packer head 26 and is held in fixedposition therewith by shear pin 32, which prevents vertical movement ofthe mandrel with respect to upper travel collar 2l), during the loweringof the tool into a borehole and until pin 32 is sheared in a mannerhereinafter described. A mandrel lock-nut 34 is connected to the upperend of mandrel 30 conveniently by threads 36. When shear pin 32 issheared, mandrel locknut 34 has Vertical travel within upper travelcollar 2li lbetween head 25 of travel adjustment screw 24 and the uppershoulder 27 of packer head 26. Sealing means 3S are convenientlyprovided in packer head 26 to provide a slidable and sealingrelationship between the outer wall of mandrel 3i) and the inner passageof packer head 26.

`A plate retaining sleeve 40 is positioned around the lower end ofmandrel 30. A plate reversing sleeve 42 is positioned about the lowerend position of plate retaining sleeve 4t). The lower end of mandrel 30,plate retaining sleeve '40 and plate reversing sleeve 4Z are threadablyconnected to a mandrel nut 44 at 46, 48 and 50, respectively. Anchor nut66 is screwed into the lower end of lower travel collar S2 at threads84.

Mandrel nut 44 is adapted to slidably fit within a lower travel collar52. During lowering operations, shear pins 54 retain mandrel nut 44 in axed position with lower travel collar 52. Shear pin 54 is of lessstrength than shear pin 32. The reasons for this will become apparentwhen the operations of the device are discussed.

A lower packer expansion head 60 surrounds the outer periphery of theupper end of lower travel collar 52 and is connected thereto by thread62. On the exterior and at the top of plate retaining sleeve 40 is platespreader 56. Plate spreader 56 preferably has a beveled downwardly andoutwardly facing shoulder 5S.

Positioned between packer head 26 and plate spreader 56 is a packersection 65 including a plurality of resilient packing elements 64.Resilient packing elements 64 are of a nature that, when compressedaxially', will expand laterally and upon such compression beingreleased, will contract substantially to their original shape. Apreferred material for these packing elements is hard rubber. As will beseen, it is especially preferred that the packing elements at the topand bottom be made of a harder material than the intermediate packingelements.

A plurality of folded metal plates 68 having center apertures as moreclearly seen in FIG. I3, are spaced about plate retaining sleeve 4d andare held in position thereon between plate reversing sleeve 42 and snapring 7l). Soft steel that will not break upon bending has been found tobe quite satisfactory for use in these plates `6d. One-sixteenth inchhas also been found to be a convenient thickness for the plates. Thenumber of plates will vary, depending upon several factors such as theamount of weight required to compress packing elements 64, as well asthe differential pressure ultimately to be across the packer section 65..The plates 68 are usually just slightly smaller in diameter, in a flatstate, than the diameter of the open hole. Plates 68 are also preferablystaggered so that the slots of the plates are not directly underneaththe slot in the plate above it.

The travel distance A of mandrel nut 44 and lower travel collar `52should be equal to, or greater, than the distance B plus C. Distance Bis the distance from the base of the lowest plate 68 to the top of lowerpacker head 6i) when mandrel nut 44 is in its uppermost position p inlower travel collar S2. Distance C is the distance betweenA snap ring 70andl the lower base of plate spreader '56, when in a position shown inFIG. 1. The travel distance D of mandrel nut 34 in upper travel collar20' is at least equal to and preferably greater than the expectedcontraction of packing elements 64.

A standpipe 80 is secured to anchor nut 66 as by threads 72. The lengthof standpipe 8ll-is selected so as to support the assembly suchV thatthe packing elements will pack 'olf the borehole at the desiredlocation. In the apparatus vshown in FIG. I1B, standpipe 80A hasperforations 74 through which fluid may be produced from that section ofthe formation beneath packing elements 64 after they are expanded.

Having described the structural features of the preiferred embodiment ofthis invention showing the best imode contemplated for the practicethereof, lattention is now directed toward the operation of the device.Prior to-lowering the packer assembly into the Well bore, standpipe 80of the desired length is secured to anchor nut 66 or" the packerassembly. The packer assembly, as illustrated in FIGS. 1A and 1B', isthen lowered through casing 1'0 by the lowering of tubing string 18. ina conventional manner. The complete packing assembly then is lowereduntil standpipe 80 borehole. A-t that point, downward force is appliedthrough the tubing string and mandrel 30 so as to shear shear pins 54.It is noted that shear pin 32 is `stronger than shear pin 54 and istherefore not ysheared at this time. Downward force is continued to beapplied through mandrel 30 forcing it downwardly. When the lower ofplates 68 contracts the upper surface of lower packer head 60, continueddownward force causes snap ring 70 to snap loosefrom engaging plateretaining sleeve 40. Plate retaining sleeve 40 and mandrel 30 are thenfree to move on downwardly through plates 68. During the travel B,shoulder 58 contracts the upper of plates 68 and forces plates 68 into asubstantially horizontal position, as shown in FIG. 4.

At this point, shear pins 32, which are of greater strength than shearpins 54, have not yet been sheared.A

Therefore, additional force is applied' through tubing string 18 toshear shear pins 32. As additional force is continued to -be appliedV tothe tubing string, upper travel collar 20. -slides downwardly overmandrel lock-nut 34 and mandrel 30. Packing elements 64 are thencompressed between packer head 26 and the support formed by the spreadplates 68. Althought not limited in any theory of operation, it appearsthat the packer segments, when compressed, form a more or less stepwiseexpansion with only the center segments contacting the borehole wall andsealing with it. This stepwise expansion of the packers is desirable-asit aids in preventing the packer section from slipping over theretaining plates, which is one of the problems in the known systems. Itis further thought vthat having the rubber harder in the end packerelement sections, as compared to the middle sections, aids in obtainingthe stepwise expansion.

The particular arrangement of the apparatus as illustrated in- FIG. 4,is very useful in shutting. olf the gas portion of the formation. Forexample, FIG. 4 shows the packer assembly is set below the gas-oilcontact 78. In this manner, the gas which flows `into the well bore 14is contained therein above the packer while oil is being produced belowthe packer through perforations 74` in standpipe 80, then up throughmandrelV 30 and into tubing 18. Support plates 68 are especially desiredif there is any substantial 'pressure differential across packingelements 64.

A packer similar to that illustrated in FIGS. 1A and 11B: has ybeenbuilt, tested in a well bore, and pulled with no diiculty. 'This packerwas used to shut off gas zones in an oil well which had 9" open holebelow 7" casing which has an internal diameter of 6%". Seventeen plateswere used having an expanded diameter of 8`1/z. The plates were TA6"thick and were made of mild steel. There rests on the bottom `of thewereseven packer elements, each 2.375 inside diameter, 6.0 outside diameter,and 6.5. in height. The open hole below the casing was successfullypacked olf using this packer. The pressure above the Packer was .about1,000 p.s.i. greater than the pressure below the packer.

These packers have proved quite advantageous. For example, they areeasily retrieved, as all that is necessary is to release the forceexpanding the packer elements 64 permitting them to return to theiroriginal shape. The tool is then pulled upwardly by the tubing stringand the metal plates 63 are folded downwardly in a reverse position likethat shown in FIG. 5. These packers also have sufficient strength tohold great differential pressures across rubber elements. Differentialpressures of at least 1,000 p.s.i. greater, may be encountered withoutditiiculty. It is also noted that the packers are expanded mechanicallyand are not dependent upon hydraulic pressures held by back checkvalves, etc.

In some instances it will be desired to produce from above the expandedpacking elements, such as in the case of shutting otl water productionfrom oil production. In such a case, it may be desired that foldedpacker plates similar to plates 68 be provided above packer section 65.A suitable means for providing folding plates above the packing sectionis illustratedVr in FIG. 6. When production is from that part of theformation above the packer assembly, it is especially desirable to havea series of folded plates positioned above the packer element 64. Thisaids in holding the packers in place as in this example when the well isproducing, the pressure is greater below the packer assembly than above.

A series of folded plates 82 are positioned about an upper platereceiving sleeve 84 which is placed about the upper end portion ofmandrel 30. Plates 82 are held in place by snap ring 86 above the platesand external shoulder element 88 of sleeve 84 below the rings. Shoulderelement 88 may be yan integral part of sleevev 84.

Upper travel collar 90 is a modification of upper travel collar 20illustrated in FIG. 14A. Upper travel collar 90 has an upper internalannular shoulder 92 and a lower internal annular Ishoulder 94. As willbe more clearly shown, shoulder member 92 and internal shoulder member94 are spaced apart a sufficient distance to permit the horizontalexpansion of folded plates 82.

Sleeve 84` has an external annular shoulder 96 which fits into uppertravel collar 90 and has free vertical movement between the uppershoulder 92 and the lower internal shoulder 94. The lower end of uppertravel collar 90 hasa downward, preferably rounded, shoulder 98 which,as will be seen, is used for spreading plates 82.

Shear pin 10) holds sleeve 84 rigid with respect to mandrel 30. Shearpin is similar to shear pin 32 and likewise is stronger than shear pinl54. Shear pin 108 connects lock-nut 109 on the upper end of mandrel 30to travel collar 90. Shear pin 108 is preferably stronger than shear pin32, but weaker than shear pin 100. When the lower plate means are usedon the same apparatus as the upper plates, shear pin 108 insures thatplates 82 will not prematurely spread.

If it is desired to use the apparatus shown in FIG. 6 to produce fluidfrom above the packer preferentially to fluid beneath the packer, aremovable plug 102 is inserted in the upper end of mandrel 30.Perforations 164 are 'also Iprovided in tubing 18. The lower portion ofthe packer assembly, as illustrated in FIG. l-B, may also be lused withthe apparatus illustrated in FIG. 6 as the upper portion thereof.

The operation of a packer assembly which has upper folded plate means 82is similar to that described above for the apparatus in FIGS. l-A andl-B. When going into the hole, sleeve 84 is supported from upper travelcollar 950 through shear pin .100', mandrel 30 and shear pin 198. Whenstandpipe Sti rests on the bottom of the borehole, las illustrated inFIG. 1-B, downward force on the tubing str-ing 18 through upper travelcollar 9i), and

mandrel 30 shears lower shear pin 54. After shear pin 54 has beensheared, continued downward movement of mandrel 30 expands lower plates68 as described above in connection with FlGS. l-A and l-B.

Addition-al downward force on tubing `18 will shear shear pin 108.Continued downward movement of tubing 18 causes shoulder 9S to spread orexpand folded plates 82 which are preven ed from downward movement byshoulder 82 of sleeve S4.

At this stage of the operation, both upper plates 32 and lower plates 68have been spread. Further downward movement of tubing 13 will shearshear pin lili). Further downward movement of tubing 18 then compressespacking elements 64.

It is to lbe noted that packer ring 106 on top of the top of packingelements 64 is spaced downwardly from shoulder 38 when sleeve 84 is inits upper position, as illustrated in FIG. 6. This spaced distance E issuliicient to allow plates 82 to be folded downwardly upon contact withthe lower shoulder 101 of casing 10 when the device is pulled out of thehole.

It may be desirable to use upper plate 8.2 when it is desired to producefrom below packer section 65. In such case, perforations 164 are notformed, or if formed, then plugged. Plug 162 is also removed and sealingmeans 103, such as O-ring, are provided lbetween shoulders 92 and 94 andsleeve 84; seals 110, such as O-rings, are also used between mandrel 30and sleeve 84.

While there are above disclosed but a limited number of embodiments ofthe system of the invention herein presented, it is possible to producestill other embodiments without departing from the inventors concept asherein disclosed. lt is therefore desired that only such limitations beimposed on the impending claims as are stated therein.

What is claimed is:

1. A well packer for use in an open hole beneath the cased portion of awell bore lwhich comprises: a mandrel means; a plurality of annularpacking elements positioned about said mandrel means and longitudinallyadjacent to each other; folded packer support plates, support meanssupporting said plates at the lower end of said mandrel means below saidpacking elements; aplate spreader above said plates; means supportingsaid plate spreader adjacent said annular packing elements a platereversing sleeve positioned about said mandrel means below said plates;a lower travel collar; a mandrel nut attachable to the lower end of saidmandrel means and longitudinally slidable within said lower travelcollar; means to retain said lower mandrel nut in said travel collar; ashear pin holding said mandrel means to said lower travel collar; andmeans to longitudinally compress said packing elements against saidplates whereby said packers are expanded laterally against the walls ofsaid well bore.

2. An apparatus as defined in claim 1 in which the interior of saidlower travel collar is in communication with the well bore beneath saidpacker elements.

3. A well packer for use in an open hola beneath a eased portion of awell bore in which a string of tubing is suspended which comprises: amandrel; a plurality of annular packing elements positioned about saidmandrel and longitudinally adjacent to each other; an upper travelcollar adapted to be attached to the lower end of a string of tubing; alower internal `annular shoulder on the lower end of said upper travelcollar; an intermediate internal annular shoulder on the interior ofsaid upper travel collar and spaced above said lower shoulder; a locknut on the upper end of said mandrel within said travel collar abovesaid intermediate internal shoulder; means for retaining said lock nutwithin said upper travel collar above said intermediate shoulder withsaid nut having free vertical travel therein; a sleeve surrounding saidmandrel and iitted slidably and sealingly within said upper travelcollar, said sleeve having an external shoulder member slid-ablypositioned between the upper internal shoulder and the lower internalshoulder of said upper travel collar; a plurality of longitudinallyspaced folded support plates positioned about said sleeve below saidupper travel collar; a first shear pin holding said sleeve rigid withrespect to said mandrel; :a second shear pin holding said lock nut rigidwith respect to said upper travel collar, said second shear pin beingweaker than said li-rst shear pin; and means to longitudinally compresssaid packing elements against said plates whereby said packing elementsare expanded laterally against the walls of said well bore.

4. An apparatus as defined in claim 3 in which the interior of saidupper t-ravel collar is in communication with the well bore above saidpacker elements.

5. A well packer for use in an open hole beneath the cased portion ofthe well bore in which a string of tubing is suspended which comprises:a mandrel; a plurality of annular packing elements positioned about saidmandrel and longitudinally adjacent to each other; an upper travelcollar adapted to be attached to the lower end of a string of tubing; asleeve slidably and sealingly mounted about the upper end of saidmandrel, said sleeve being sealingly and slidably mounted in saidcollar; iirst frangible means adapted to hold said sleeve rigidly tosaid mandrel; means to limit the vertical longitudinal movement of saidsleeve with respect to said collar; second means to limit the verticallongitudinal movement of said mandrel with respect to said collar;second frangible means to hold said mandrel rigid with respect to saidtravel collar; a plurality of longitudinally spaced folded supportplates positioned about said sleeve below said upper travel collar; andmeans to longitudinally compress said packing elements against saidplates whereby said packers are expanded laterally against the w-alls ofsaid well bore.

6. A well packer for use in an open hole beneath the cased portion ofthe -well which comprises: a mandrel; a plurality of annular packingelements positioned about said mandrel; folded packer support plates;means supporting said support plates at the lower end of said mandrel.below said packing elements; a plate spreader; means supporting saidplate spreader about said. mandrel beneath said annular packing elementsand above said plates; a lower travel collar; means to limit thelongitudinal vertical movement of said mandrel within said lower travelcollar; rst frangible means holding said mandrel with respect to saidlower travel collar; fan upper travel collar adapted to slidably receivesaid mandrel, said upper travel collar having -a packer head means at.its lower end; means to limit the longitudinal movement of said mandrelwithin said upper tr-avel collar; second frangible means holding saidmandrel to said upper travel collar, said second frangible means beingstronger than said first frangible means.

7. A packer for use in lan open well bore beneath a cased portion ofsaid well bore which comprises: an upper travel collar adapted to beattached to the lower end of a string of tubing, a tubular mandrel, alock-nut on the upper end of said mandrel, means for retaining saidlocknut within said collar with said nut having free vertical travelywithin said collar, a packer bead attached to the lower end of saidtravel collar, sealing means for sealing said mandrel with said packerhead in a sliding and sealing relationship, 4a retaining sleeve mountedabout said mandrel, a plurality of longitudinally spaced folded supportplates positioned about said retaining sleeve, a plate spreader on saidretaining sleeve above said plates, a plurality of sectional annularpacking elements spaced about said mandrel between said plate spreaderand said packer head with adjacent elements being contiguous, a platesnap ring spaced about said yretaining sleeve below said plate spreader`and above the upper of said plurality of plates, a lower travel collar,a mandrel nut attachable to lower end of said mandrel and said retainingsleeve and longitudinally slida'ble within said lower travel collar,means to retain said mandrel nut in said lower travel col- Y 7`4 lar,rst shear pin holding said mandrel to said uppertravel, collar, secondshear pin holding said mandrel to said lower travel collar, said rstshear pin being of greater strength than said second shear pin.

References Cited in the le of this patent UNITED STATES PATENTS1,771,556 COX July 29, 1930 8 Parrish May 1, Simmons` Aug. 2-9, VanBrunt et 8l, Aug. 5, Morgan et al. Oct. 7, Lynes Mar. 13, Morrisett Oct.8, Thompson Dec. 3, ohnson et al Feb. 24,

1. A WELL PACKER FOR USE IN AN OPEN HOLE BENEATH THE CASED PORTION OF AWELL BORE WHICH COMPRISES: A MANDREL MEANS; A PLURALITY OF ANNULARPACKING ELEMENTS POSITIONED ABOUT SAID MANDREL MEANS AND LONGITUDINALLYADJACENT TO EACH OTHER; FOLDED PACKER SUPPORT PLATES, SUPPORT MEANSSUPPORTING SAID PLATES AT THE LOWER END OF SAID MANDREL MEANS BELOW SAIDPACKING ELEMENTS; A PLATE SPREADER ABOVE SAID PLATES; MEANS SUPPORTINGSAID PLATE SPREADER ADJACENT SAID ANNULAR PACKING ELEMENTS A PLATEREVERSING SLEEVE POSITIONED ABOUT SAID MANDREL MEANS BELOW SAID PLATES;A LOWER TRAVEL COLLAR; A MANDREL NUT ATTACHABLE TO THE